c++ - 有符号整数类型的大小是否可以不同于 C/C++ 中对应的无符号整数类型的大小？

Question

例如，一个实现是否可以将 sizeof(signed int) 定义为两个字节，将 sizeof(unsigned int) 定义为四个字节？我无法在 C/C++ references 中找到任何明确禁止这样做的内容，尽管类型的有符号和无符号版本的最小大小是对应的，但我看不出它们的大小应该不同的任何逻辑原因。

Answer 1

Can the size of a signed integer type differ from that of its corresponding unsigned type in C/C++?

没有。对于 C，int 和 unsigned 具有相同的大小。 Confident C++ 继承了相同的规范。

For each of the signed integer types, there is a corresponding (but different) unsigned integer type (designated with the keyword unsigned) that uses the same amount of storage (including sign information) and has the same alignment requirements.
C11dr §6.2.5 6